PROGRAMMING:The nameless of ZF series
After escaping the pursuit of Huo Qilin, ZF finds an old man vomiting blood on the side of the road. The kind-hearted ZF takes out his ancestral Shiquan Buwan and treats the old man,
Only then did I know that the old man was 50 years ago. The world's No.1 expert, nameless, heard that ZF was in trouble with the smiling demon king, and decided to pass on his life skills to ZF,
However, limited by ZF's qualification, the more internal power you pass, the more you lose. When the internal power you pass is n < = 50 years, and the skill is not lost, 100 > = n > 50, you will lose 1 success power, which is more than 100 years
Will lose 2 success power, seek ZF finally got nameless how many years of skill?
Keep one decimal place for the result
###Input format:
Unknown skill n
###Output format:
Output the actual power
###Input example:
Here is a set of inputs. For example:
```in
fifty
```
###Output example:
The corresponding output is given here. For example:
```out
fifty
```
answer：If there is no answer, please comment
Only then did I know that the old man was 50 years ago. The world's No.1 expert, nameless, heard that ZF was in trouble with the smiling demon king, and decided to pass on his life skills to ZF,
However, limited by ZF's qualification, the more internal power you pass, the more you lose. When the internal power you pass is n < = 50 years, and the skill is not lost, 100 > = n > 50, you will lose 1 success power, which is more than 100 years
Will lose 2 success power, seek ZF finally got nameless how many years of skill?
Keep one decimal place for the result
###Input format:
Unknown skill n
###Output format:
Output the actual power
###Input example:
Here is a set of inputs. For example:
```in
fifty
```
###Output example:
The corresponding output is given here. For example:
```out
fifty
```
answer：If there is no answer, please comment